Small Modular Reactors (SMRs) are a relatively familiar topic in the realm of energy production, but there is no doubt they are growing in support and use. While they are similar to a traditional reactor, their size and function is what makes them different. They’re designed to be put together almost like Legos, instead of being one large reactor that operates at full power, which allows for a new flexibility in use.

How Small Modular Reactors Work

SMRs operate at a third or less of traditional reactor output, totaling in power capacity to about 300 megawatts per unit. SMRs produce energy through nuclear fission, the process of splitting an atom to release energy in the form of heat and radiation. The thermal energy is then used to generate electrical power. While this process is essentially the same in all SMRs, there is a variety of technologies that can be used to accomplish the generation of power, including coolants such as gas, liquid metal or molten salt.

Image Credit: International Atomic Energy Agency

Advantages of Small Modular Reactors

While small modular reactors are similar to traditional reactors, there are a multitude of advantages. Many times, larger reactors are built on site and are customized to a particular location; however, with the smaller size of SMRs, design and production is cheaper and quicker. Their size also allows them to suitably provide reliable electricity to a variety of areas, including underwater, underground and remote regions. SMRs can be used to supply energy or act as a backup to other reactors as need arises. They also are resistant to disruption from natural disaster events due to passive safety features. A main reason these reactors are growing in popularity is their favorable environmental impact relative to other generation technologies. Not only are SMRs useful for reducing carbon emissions, but they take up a fraction of land in comparison to wind or solar installations.

Energy 101: Small Modular Reactors

Support for SMRs

In 2012, the SMR Licensing Technical Support program was created to work directly with research institutions, national laboratories and academic public and private partnerships to promote the development of SMRs. The focus was to ensure that the reactors would be safe, secure and operational. Later in 2019, an expansion of the program was initiated through the establishment of the Advanced SMR R&D program. This program specifically supports the research, development and deployment activities to accelerate national and international availability of SMRs. Most recently in July 2021, Oak Ridge National Laboratory (ORNL) and Analysis and Measurement Services Corporation (AMS) completed a looping performance test to research the sensors for advanced light-weight SMRs. A thermosyphon loop and specialized stem loop were created to examine the operating conditions for when natural water circulation is used to cool the reactor. They also assessed the response time needed to detect coolant condition changes in order to determine what is necessary for initiating a safe, automatic shut down. Findings are still being finalized for this study.

Tax Benefits

The 2005 Energy Policy Act established a production tax credit eligible for nuclear power facilities to be awarded 1.8 cents per kilowatt-hour of electricity produced during the first eight years of operation. The Zero-Emission Nuclear Power Production Credit Act was introduced in June 2021 and co-sponsored by 21 members in the House of Representatives. This bill would make merchant nuclear plant owners and operators eligible for the same tax credit wind operators receive, which is 1.5 cent/kilowatt hour credit ($15/megawatt hour).

Use of Small Modular Reactors

While nuclear reactors have been in existence worldwide since the 1950s, the development of SMRs has been growing more recently, as shown by the World Nuclear Association list below. Currently, there are more than 70 commercial SMR designs globally. These SMRs cover of a variety of applications, including electricity, hybrid energy systems, heating, water desalinisation and steam for industrial applications.

Today, we are going to cover the current SMR happenings in four main countries: the US, UK, Canada and China.

The US

While the United States has been funding development of SMRs for the last ten years, the company who has received the most support is NuScale, with over $450 million dollars in matched funding for technology design and development. Construction of the first NuScale SMR should be completed in 2027. This project is coordinated through Utah Associated Municipal Power Systems (UAMPS) and will be developed at the Idaho National Laboratory. Once operational (projected to happen in 2029) the power generated will be portioned out to the U.S. Department of Energy and UAMPS member facilities. With the design of this SMR, possibilities could open up on a wider scale due to the minimization of uncertainty of utility and design certification.

The UK

The first UK SMR, Rolls-Royce SMR, is expected to be operational in 2030. The initial development and funding was completed in 2021 and outlined that this SMR would provide power to one million homes. Once this is completed, Rolls-Royce SMR Ltd will begin to construct 16 duplicate SMRs, which they hope to have operational by 2050. It has been projected that these power stations will create 40,000 jobs and boost the economy by $70 billion.

Rolls Royce SMR Rendering, Image Credit: Nuclear AMRC


Canada established an Action Plan in 2020 that detailed their vision of creating SMRs as a means to achieving their net-zero emissions by 2050 goal. The plan includes a country-wide partnership of government organizations, Indigenous groups, industry groups, and utility and civil society organizations. The first Canadian SMR project is being completed by Global First Power (GFP), a commercial partnership between OPG and USNC-Power, and is currently undergoing an environmental review. This SMR is expected to provide power by 2026.


In December 2021, China became first in the world to operate a commercial, onshore SMR. Created by China Huaneng Group Co., this 200-megawatt unit 1 reactor powers an area in Shandong province. The reactor produces power using helium and is equipped with an automatic safety feature that shuts the system down if a problem arises. A second SMR is on schedule to be operational in 2022 after tests are completed. This is just the beginning for China, as they expect to invest $40 billion in nuclear power over the next 15 years.

China’s Demonstration SMR, Image Credit: CNNC


Small modular reactors are becoming increasingly popular globally as they provide many benefits over traditional reactors. Many of the advantages enjoyed by SMRs are related to their smaller size and shortened construction timelines. This makes them easier and faster to install, and also allows for more customization to the use case. Passive safety features of SMRs offer significant promise to reduce the likelihood of loss-of-coolant accidents when external electricity is not available. Thanks to these benefits and others, small modular reactors are poised for a bright future in the energy market, with growth in the breadth of designs and new deployments happening across the world.

Andrew Schaper is a professional engineer and principal of Schaper Energy Consulting.  His practice focuses on advisory in oil and gas, sustainable energy and carbon strategies.

For consulting or media inquiries, please contact  To learn more about Schaper Energy Consulting, visit our website here.